MainActivity如下:
package cc.c;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.List;
import android.app.Activity;
import android.app.ActivityManager;
import android.app.ActivityManager.MemoryInfo;
import android.app.ActivityManager.RunningAppProcessInfo;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
/**
* Demo描述:
* 清理手机内存
*
* 参考资料:
* 1 http://blog.30c.org/1816.html
* 2 http://www.cnblogs.com/helloandroid/archive/2011/10/14/2212334.html
* Thank you very much
*
* 注意权限:
* <uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES" />
*
*/
public class MainActivity extends Activity {
private TextView mTotalMemoryTextView;
private TextView mAvailMemoryTextView;
private Button mCleanButton;
private TextView mCleanInfoTextView;
private ActivityManager mActivityManager;
private StringBuffer mCleanInfoStringBuffer;
private long availMemory;
private long totalMemory;
private List<RunningAppProcessInfo> mRunningAppProcessInfoList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
init();
}
private void init() {
mCleanInfoStringBuffer = new StringBuffer();
mActivityManager=(ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
mTotalMemoryTextView = (TextView) findViewById(R.id.totalMemoryTextView);
mAvailMemoryTextView = (TextView) findViewById(R.id.availMemoryTextView);
mCleanInfoTextView = (TextView) findViewById(R.id.cleanInfoTextView);
mCleanButton = (Button) findViewById(R.id.cleanButton);
totalMemory = getTotalMemory();
availMemory = getAvailMemory();
mTotalMemoryTextView.setText(totalMemory + "MB");
mAvailMemoryTextView.setText(availMemory + "MB");
mCleanButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
RunningAppProcessInfo runningAppProcessInfo=null;
mRunningAppProcessInfoList= mActivityManager.getRunningAppProcesses();
//List<ActivityManager.RunningServiceInfo> serviceInfos = mActivityManager.getRunningServices(100);
if (mRunningAppProcessInfoList != null) {
for (int i = 0; i < mRunningAppProcessInfoList.size(); ++i) {
runningAppProcessInfo= mRunningAppProcessInfoList.get(i);
// 一般数值大于RunningAppProcessInfo.IMPORTANCE_SERVICE
// 的进程即为长时间未使用进程或者空进程
// 一般数值大于RunningAppProcessInfo.IMPORTANCE_VISIBLE
// 的进程都是非可见进程,即在后台运行
if (runningAppProcessInfo.importance > RunningAppProcessInfo.IMPORTANCE_VISIBLE) {
String[] pkgList = runningAppProcessInfo.pkgList;
for (int j = 0; j < pkgList.length; ++j) {
mActivityManager.killBackgroundProcesses(pkgList[j]);
mCleanInfoStringBuffer.append(pkgList[j] + " is killed...\n");
mCleanInfoTextView.setText(mCleanInfoStringBuffer.toString());
}
}
}
}
//再次获得剩余内存以计算清理值
mCleanInfoStringBuffer.append("共清理："+(getAvailMemory() - availMemory) + "MB");
mCleanInfoTextView.setText(mCleanInfoStringBuffer.toString());
mAvailMemoryTextView.setText(getAvailMemory() + "MB");
}
});
}
private long getTotalMemory() {
//系统的内存信息文件
String filePath = "/proc/meminfo";
String lineString;
String[] stringArray;
long totalMemory = 0;
try {
FileReader fileReader = new FileReader(filePath);
BufferedReader bufferedReader = new BufferedReader(fileReader,1024 * 8);
//读取meminfo第一行,获取系统总内存大小
lineString = bufferedReader.readLine();
//按照空格拆分
stringArray = lineString.split("\\s+");
//获得系统总内存,单位KB
totalMemory = Integer.valueOf(stringArray[1]).intValue();
bufferedReader.close();
System.out.println("------> lineString=" + lineString+ ",stringArray[0]=" + stringArray[0] +
",stringArray[1]="+ stringArray[1] + ",stringArray[2]=" + stringArray[2]);
} catch (IOException e) {
}
return totalMemory / 1024;
}
private long getAvailMemory() {
MemoryInfo memoryInfo = new MemoryInfo();
mActivityManager.getMemoryInfo(memoryInfo);
return memoryInfo.availMem / (1024 * 1024);
}
}
main.xml如下:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin" >
<TextView
android:id="@+id/totalTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="系统内存："
android:textSize="25sp"
android:textColor="#1cf109" />
<TextView
android:id="@+id/totalMemoryTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="@id/totalTextView"
android:textSize="25sp"
android:textColor="#1cf109" />
<TextView
android:id="@+id/availTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/totalTextView"
android:text="可用内存："
android:textSize="25sp"
android:textColor="#5c0169" />
<TextView
android:id="@+id/availMemoryTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/totalTextView"
android:layout_toRightOf="@id/availTextView"
android:textSize="25sp"
android:textColor="#5c0169" />
<Button
android:id="@+id/cleanButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/availMemoryTextView"
android:textSize="25sp"
android:text="清理内存" />
<ScrollView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/cleanButton" >
<TextView
android:id="@+id/cleanInfoTextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</ScrollView>
</RelativeLayout>
PS:更好的方式请参见Android清理设备内存详细完整示例(一)
